In the chapter "In Which Kanga and Baby Roo Come to the Forest and Piglet Has a Bath", the Hundred Acre Wood residents are suspicious of the newcomers and devise a plan to distract Kanga and swap Roo for Piglet and say "Ah-ha!" when Kanga asks where Roo is. The plan fails as Rabbit has grown fond of Roo, and Pooh Bear had decided to be like Kanga and was practicing jumps. Kanga pretends Piglet is Roo as a joke and gives him the extract of malt, declaring "You don't want to grow up to be small and weak like Piglet."
In the chapter "In Which Tigger Comes to the Forest and Has Breakfast", after finding nothing for breakfast he enjoys, Tigger sees Roo about to be given his strengthening medicine, but eats it instead, declaring tiggers like it. Roo is excited and says "He's taken my medicine!". The extract of malt is then put into sandwiches for Tigger in the chapter "In Which it is Shown That Tiggers Don't Climb Trees".